Horseradish tree (Moringa oleifera) is one of 13 species in the genus Moringa from Africa. The genus name is derived from the Tamil word for drumstick, one of the alternative names in English, referring to the long immature pods which are used as a vegetable (I first came across it as an Indian vegetable on a market in Fiji in the early 90s where it was called horseradish tree). However, it has multiple uses also including leaves (as a protein rich vegetable), for its flowers, immature seeds, roasted or fried mature seeds (an oil is also extracted), roots (tastes like horseradish) and also seed sprouts! Different cultivars have been developed for different uses. There are other species which are also used, including Moringa stenopetala and M. ovalifolia.
Although it’s a tree that can grow to 12m tall, it can also be grown as a cut-and-come-again house plant, which is the way I’ve grown it (for the leaves) in my old office in Trondheim (see the album of pictures below)! In fact, it is also grown commercially as an annual.